The following is a description of concepts relating to the field of the invention and a more detailed specification of their meaning.
The biological component enrichment unit refers to a set of apparatuses suitable for the growing, isolation, purification, enrichment and determination of bacteria, viruses, proteins and nucleic acids.
Particles or magnetic particles refer to all objects that can be moved by means of magnetism, directly or by linking them with a material to be magnetised. Many different particles are known to be movable by means of a magnet, and the applications in which they are used also vary greatly. The size of the particles used in e.g. microbiology ranges from 0.01 to 100 μm, and most typically from 0.05 to 10 μm. Such particles include e.g. particles containing ferromagnetic, paramagnetic or superparamagnetic material. The particles may also be magnetic in themselves, in which case they can be moved by means of any ferromagnetic object.
The magnetic tool or apparatus intended for handling the particles has an element that uses magnetism, hereinafter referred to as a magnet. It may be a permanent magnet or an electromagnet that attracts magnetisable or magnetic particles. Usually, the magnet is most preferably a round bar magnet. It may also be an object of another shape. The magnet may also be comprised of one or several objects, such as magnets or ferromagnetic objects.
The magnet must be overlaid with a protective membrane or coating that protects the magnet from harmful conditions and enables the handling, such as binding and release, of the particles. The structure of the protective membrane may vary greatly and it may be, e.g., a thin film of flexible or stretchable material or a protection that is made, say, from rigid plastic.
Particles are generally used as solid phases for binding various kinds of biological components, such as nucleic acids, proteins, bacteria or cells. The effective enrichment of e.g. pathogenic bacteria from a large to a small sample volume is a critical factor, as it directly influences the sensitivity and analysis time of bacterial determination.
No sufficiently efficient method is currently available for concentrating biological components by means of particles from a large volume to a small volume.